An ice maker is an apparatus for making ice in an appropriate size and discharging the ice by a required amount when a user needs the ice. An ice bank is a unit of elements forming the ice maker, for receiving made ice, and discharging an appropriated amount of the received ice. Also, depending on cases, only a portion for directly freezing water to make ice may be called an ice maker, a portion for storing the made ice may be called an ice bank, and a portion for discharging an appropriate amount of the stored ice to the outside may be called a dispenser.
There are various ice makers. Among them, an ice maker annexed to a refrigerator is disclosed in Korea Patent Publication No. 2005-0056484. This document discloses an entire system of the ice maker applied to the refrigerator. This type of ice maker is annexed to a refrigerator to satisfy a reasonable demand at low price, so that convenience in utilizing the ice maker increases.
A related art driving unit of an ice bank is described in more detail. The related art driving unit of the ice bank includes a motor and a motor shaft for providing driving force, and a rotation shaft for transferring ice in the inside of the ice bank. Also, the driving unit includes a joint as a portion for connecting the motor shaft and the rotation shaft with each other. The joint serves as a portion allowing driving force of the motor to be swiftly delivered to the rotation shaft.
The joint includes a body and a driving unit protruding to an inside from the body and at which the motor shaft is hooked. The body and the driving unit are integrally formed. Here, the body and the driving unit are connected to the motor shaft and is formed by sintered monolith stainless steel to secure sufficient strength against rotational force provided by the motor. This has been indispensably required to allow the joint to endure such sufficient strength as to crack clustered ice depending on the clustering state of the ice that has been broken into pieces in the inside of the ice bank.
Also, the body and the outer surface of the driving unit are plated with Ni—P to prevent the body and the driving unit from being corroded by water.
However, the above-described joint is formed by sintered monolith stainless steel and thus is heavy. Also, since the outer surface of the joint should be plated with Ni—P, processibility reduces and corrosion occurs when the plating is exfoliated.